With the improvement of people's standard of living, the jewelries as people's ornaments are more and more widely used, in which the diamond jewelries are especially prominent. In a quality evaluation of the diamond, four aspects of color, clarity, carat, and cut are considered primarily. Because their English names all begin with the letter of “C”, these four standards are called 4C for diamond. Because the color, clarity and carat are its own properties during diamond formation and cannot be altered, only cutting can endow the diamond with better quality and value and endow the diamond with more brilliant radiance.
The US application US2009/0056374A discloses a Gemstone Facet Configuration; the gemstone have a table facet 118, eight trapezoidal facets 120, eight irregular-hexagonal facets 122, eight irregular-pentagonal facets 124 and sixteen triangular crown-facets 126; the structure of the gemstone is irregular and the cutting ratio is not good enough.
The U.S. application D616,785S discloses a Round Cut, which has a table facet, twelve trapezoidal facets, twelve hexagonal facets, twelve pentagonal facets and twenty four triangular crown-facets. There are no cutting parameters of the gemstone for reference and the structure of the pavilion facet is quite simple.